Oligo(tyrosine sulfate)s as heparin pentasaccharide mimic: Evaluation by surface noncovalent affinity mass spectrometry

Since the discovery of anti-HIV activity in oligo(tyrosine sulfate)s in our laboratory, we have been interested in their potential as heparin pentasaccharide mimics. In this study, we investigated their interactions with synthetic heparin-binding peptides, derived from human antithrombin III (hAT III) and heparin-interacting protein (HIP), using surface noncovalent affinity mass spectrometry. We compared binding affinities to those heparin-binding peptides between oligo(tyrosine sulfate)s and several known sulfated compounds and found that oligo(tyrosine sulfate)s bind to hAT III (123-139) more strongly than a heparin-derived hexasaccharide dp6. Moreover, we found longer oligo(tyrosine sulfate) has higher binding affinity to hAT III (123-139).